The present invention relates to the general field of biological test appliances suitable for measuring or evaluating a biological variable at a point of care.
Such appliances are generally installed away from a laboratory, and frequently in an ambulatory service or even at a patient's home. Such appliances are generally portable, sometimes precalibrated, fast, and easy to use.
The invention applies more particularly to all point-of-care appliances for testing glycemia and it also applies to point-of-care testing of other biological parameters that can be measured by a biological test appliance at the point of care, i.e. away from a laboratory. Such parameters include blood gas, measuring hematocrits, measuring lactates, measuring urinary or blood ionograms, measuring urinary glucose, measuring uric acid, measuring cholesterol, measuring triglycerides, and any other physicochemical and/or biological parameter that is useful for diagnosis and decision making concerning the care to be given to a patient.
Depending on their construction, such point-of-care biological test appliances may operate continuously, or discretely.
The invention relates particularly to such point-of-care biological test appliances where it is useful or even essential to monitor their quality. Since such appliances are used in distinct places, sometimes on private premises, it is necessary to inspect that the values given by such appliances are correct.
At present, in order to inspect such a point-of-care biological test appliance, a measurement is performed by the appliance with the result of the measurement being sent to the laboratory, and simultaneously a venous blood sample is taken for sending to the laboratory as well as the measurement performed by the point-of-care biological test appliance.
A biologist then measures the biological value in the venous blood and compares the values that have been obtained in order to determine whether the point-of-care biological test appliance is functioning correctly or is functioning erroneously.
Insofar as point-of-care biological test appliances measuring glycemia generally use capillary blood, whereas the sample sent to the laboratory is venous blood, there is necessarily a bias between the values measured for those two types of blood.
This bias is made uncertain and is made greater by the fact that the test means are necessarily different and make use of different principles. Uncertainty concerning the real value of the bias gives rise to potential hazard if the point-of-care biological test appliance is declared valid when in fact the measurements it is making are significantly wrong. The inspection performed in that way can only be approximate and ultimately relies on the expertise of the biologist.
Nowadays another technique for inspecting a point-of-care biological test appliance exists and is recommended by the manufacturers of such appliances. Inspection is based on using a solution made available by the manufacturer for inspecting the point-of-care appliance.
Once the manufacturer has acquired a measurement for the solution, the value as measured is compared with ranges that are also supplied by the manufacturer.
This makes inspection direct, but it does not make it possible to evaluate the point-of-care biological test appliance relative to other appliances of other types and possibly operating on other principles.
It is also necessary to have a special control solution for each type of appliance in order to inspect all of the point-of-care biological test appliances in a group. That is difficult to implement and constitutes a source of error. It can therefore be harmful when several different types of point-of-care biological test appliance are in use by a given hospital service and when it is necessary to inspect their reliability and uniformity.
The invention thus proposes providing a method that supplements inspecting a point-of-care biological test appliance with the solution supplied by the manufacturer, and for this purpose the invention proposes an automatic technique that improves and simplifies inspection by performing measurements in parallel on the point-of-care biological test appliance and on a biological test appliance situated in a laboratory.